If you browse around many gadget shops, you will have invariably seen CD clocks for sale, usually in the $20 range, and thought, "nice, but too much money". Or, if you frequent memorabilia stores you'll see Elvis CD wall clocks. These use the same mechanism, but have a picture CD of Elvis on them instead, retailing in the $40 range. If either sound appealing, but both sound overpriced, here's a quick makers guide to creating your own.
Step 1: Preparing the mechanism
First, buy a cheap clock mechanism. These are easier to find than you think. Visit any thrift or pound store and you'll probably find some garish clocks for sale with perfectly good mechanisms, but flimsy and unappealing surrounds. I live in the UK, and bought one going cheap for a pound just after England had been knocked out of the World Cup. Again. Hobby stores and electronics shops will probably sell you the exact same mechanism for $5-8. Get one with the longest hands you can find.
Step 2: Dismantle
Second, dismantle the whole unit. Removing the hands first will allow you to slide the surround off easily, as it is often glued to the mechanism itself. The surround often has the screw hole for mounting, which the mechanism lacks. But don't worry about lose such vital functionality because, without this hulking piece of plastic, it can be secured very effectively with just blu-tack. One of the clocks in my house is still going strong since the last World Cup!